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#include <iostream>
#include <vector>
#include <algorithm>
#include <queue>
#include <stack>
#include <deque>
#include <set>
#include <map>
#include <string>
#include <cmath>
#include <numeric>

int main() {
    std::ios_base::sync_with_stdio(false);
    std::cin.tie(NULL);

    int k, n_1;
    std::cin >> k >> n_1;
    std::vector<std::vector<std::vector<int>>> tree(k + 2);
    std::vector<std::vector<int>> dp(k + 2);
    std::vector<int> days;

    days.resize(k + 2, 0);
    dp[1].resize(n_1 + 2, {});
    tree[1].resize(n_1 + 2, {});
    days[1] = n_1;

    for (int i = 2; i <= k; i++) {
        std::cin >> days[i];
        tree[i].resize(days[i] + 2, {});
        dp[i].resize(days[i] + 2, 0);
        for (int j = 1; j <= days[i]; j++) {
            int a;
            std::cin >> a;
            if (a > 0) {
                tree[i - 1][a].push_back(j);
            }
        }
    }

    int result = 0; // max from all the layers

    // traverse from the back to the beginning
    for (int i = k; i >= 1; i--) {
        int curr_result = 0;
        // traverse one layer
        for (int j = 1; j <= days[i]; j++) {
            int sum_children = 0;
            if (tree[i][j].empty()) {
                sum_children = 1;
            } else {
                for (const int child : tree[i][j]) {
                    sum_children += dp[i + 1][child];
                }
            }
            dp[i][j] = sum_children;
            curr_result += sum_children;
        }
        result = std::max(result, curr_result);
    }

    std::cout << result << "\n";
    return 0;
}